#if语句
people=20
cats=30
dogs=15


if people < cats:
   print("Too many cats! The world is doomed!")

if people > cats:
   print("Not many cats! The world is saved!")

if people < dogs:
   print("The world is drooled on!")

if people > dogs:
   print("The world is dry!")


dogs += 5

if people >= dogs:
   print("people are grater than or equal to dogs.")

if people <= dogs:
   print("People are less than or equal to dogs.")


if people == dogs:
   print("People are dogs.")
